LOCATING POINTS
the holes in the bushing A and casting C, Fig. 22, in which the wedge slides.    This practically makes the wedge self-aligning.
Locating from Finished Holes. — If the work to be finished in the jig has some holes already finished, it is sometimes most satisfactory to locate the work by these holes, which may be done by means of studs or plugs similar to the one shown in Fig. 3, which then enter the holes; preferably, these studs should be ground and hardened to the standard size of the hole. If the finished hole should be of a character that varies somewhat in size, expansion studs with bushings may be used. These studs

Machinery
Fig. 23.   The Adopted Form of Adjustable Wedge Stop
may be of a great many different designs and styles, but, as a rule, they always work on the same principle as the one shown in Fig. 24. In this, A is the bushing, fitting the finished hole in the work. This bushing is split in several different ways, either by having one slot cut entirely through it, and two more slots cut to within a short distance of the outside periphery, or by having several slots cut from the top and from the bottom, alternating, but not cut entirely through the full length of the bushing. The method of splitting, however, in every case, accomplishes the same object, that of making the bushing capable